So, let’s assume Christian theism is true, and go on to see if it rationally grounds the minimal requirements for morality.

Evaluation

1) Objective moral values: GROUNDED

Objective moral values are grounded in God’s unchanging nature. His own character is the standard for what counts as good and evil. The standard is not variable, but fixed, by God’s unchanging nature.

2) Objective moral duties: GROUNDED

Objective moral duties are grounded in God’s commands, which flow from the values in his nature and become duties for his creatures.

3) Moral accountability: GROUNDED

On Christian theism, there is a final judgment after death in which good will be rewarded and evil will be punished, proportionally.

4) Free will: GROUNDED

On Christian theism, each person is a union of a material body and a non-material mind / soul. The actions of the non-material mind / soul are not determined by material processes, and humans are therefore able to make real choices.

5) Ultimate significance: GROUNDED

On Christian theism, death is not the end of the story. Each moral action performed is part of on ongoing relationships with God, and people. So, no action is meaningless, because all your actions relate to God, who exists eternally, or to other people, who also exist eternally into the future.

Conclusion

Christian theism grounds all of the minimal requirements needed for rational morality. In Christian theism, we see the fusion of prudence (Acting morally is what I am designed to do in order to flourish, i.e. – “eudaimonia”) and submission to a loving God (I will act morally to respect God, because he loves me the most). More to come on the latter point!

You can get the full story on the requirements for rational morality in a published, peer-reviewed paper written by William Lane Craig here. You can also hear and see him present the paper to an audience of students and faculty at the Georgia Institute of Technology in 2008. The audio is clipped at 67 minutes, the video is the full 84 minutes. There is 45 minutes of Q&A, with many atheist challengers.

The video of this lecture is the best material you can get on this issue, and the Q&A from the hostile audience is vital to the lesson. More debates on atheism and morality can be found on the debate and lecture page.

You can find a post contrasting the morality of an authentic, consistent Christian with an authentic, consistent non-Christian here. A post examining how atheism is responsible for the deaths of 100 million innocent people in the 20th century alone is here. A post analyzing the tiny number of deaths that religion was responsible for is here.